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ELECTRICAL SYSTEMS
SECTION 10-1
INSTRUMENTS AND CLOCK
CONTENTS OF SECTION 1
O-J
INSTRUMENTS
10-97
..
Para!lraph
Subiect
Page
10-65
Charge Indicator, Tempera-
ture Gauge, Oil Pressure Gauge 10-97
10-66
Electric Clock
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.
.
.
.
.
. . .
. .
. .
.
10-98
Paragraph
SubJect
Page
10-67
Gasoline Gauge-Dash and
Tank Units
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.
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.
. .
.
.
. .
.
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. 10-100
10-68
Speedometer
10-101
Bulletin No.
Page No.
SERVICE BULLETIN REFERENCE
SUBJECT
10-65 CHARGE INDICATOR,
TEMPERATURE GAUGE, OIL
PRESSURE GAUGE
a.
Charge Indicator (Ammeter)
The AC charge indicator located in the in-
strument cluster is similar to an ammeter;
however, the scale is not graduated in amperes,
therefore the indicator does not show the
amount of current flowing. The current re-
quired to move the pointer against the stop is
15 amperes for both charge and discharge. The
pointer is provided with a dampener, consist-
ing of Silicon-Jell on the front pivot, to reduce
pointer fluctuation when the voltage regulator
is functioning.
The charge indicator will indicate "charge"
when the battery is being charged and "dis-
charge" when the battery is being discharged.
It gives an indication of the state of charge of
the battery, since it shows a relatively high
charging rate when the battery is low, and a
low charging rate when the battery is near
full charge. Immediately after cranking the en-
gine, the charge indicator will be well over on
the "charge" or plus
(
+)
side for a short time,
if lights and accessories are turned off. As the
energy used in cranking is restored to the bat-
tery the pointer will move back toward zero
but will stay slightly on the plus
(
+)
side.
If the battery is low, however, the charge in-
dicator will show a high charging rate for a
considerable period of time.
The charge indicator does not indicate charg-
ing rate of the generator since energy supplied
by generator to electrical units other than the
battery and horns does not pass through the
indicator. At speeds above 15 MPH, with lights
and accessories turned on, the indicator may
show a low reading on the discharge side. The
indicator should never show a high discharge
reading; if it does, the generator and regulator
should be tested.
b. Temperature Gauge
The AC temperature gauge, located in the
instrument cluster below the charge indicator,
is not an electrical instrument. The heat indi-
cator is a vapor pressure type which makes use
of a sealed-in liquid, the expansion of which
creates a pressure which moves the pointer on
the gauge.
The temperature gauge is a unit assembly
consisting of a pressure gauge connected by a
capillary tube to a vapor bulb. The vapor bulb
is attached by a plug to the right rear corner of
the engine cylinder head so that it extends into
the cooling water. The heat of the water causes
the sealed-in liquid in bulb to expand in pro-
portion to temperature and exert pressure on
the gauge in instrument cluster. The gauge is
marked "COLD" and "HOT" and does not
show temperature in degrees.
The capillary tube is supported by a clip on
the dash near its connection to cylinder head.
A loop is formed in tube between clip and cylin-
der head to absorb vibration, and allow for
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